The present invention pertains generally to brake systems for trailers towed by autos and small trucks.
Typically recreational trailers, of the type commonly towed by autos and pickup trucks, are equipped with electric brakes which include solenoid operated shoes or pads. A brake control or controller in the towing vehicle utilizes a mechanism responsive to towing vehicle velocity changes to generate a signal to the trailer brakes to initiate brake operation. Such trailer braking systems normally draw a known amperage which indicates all of the solenoids in each brake system are functional, and conversely, a lesser amperage is indicative of a malfunctioning solenoid or solenoids. Heretofore, it was the practice to test trailer brakes by application of the tow vehicle's brakes. Brake problems are indicated by poor or asymmetrical braking action of the trailer brakes. The aforementioned control permitted adjustment of the current flow to suit individual driver preferences but such controllers do not indicate the status of the brake solenoids. Hence the first indication of a trailer braking problem is usually uneven braking action of the trailer or reduced braking action.